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Old 12-21-2011, 01:19 PM
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Jeffhs Jeffhs is offline
<----Zenith C845
 
Join Date: Feb 2003
Location: Fairport Harbor, Ohio (near Lake Erie)
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Quote:
Originally Posted by ClarusWorks View Post
I assume just throwing another fuse in and seeing if it works probably isn't the best idea...

You're right -- that is not the best idea on earth; in fact, it can do incredible damage, as I am about to explain. A basic rule of electronic servicing is to allow yourself one, and only one, new fuse when troubleshooting anything. If the new fuse goes, it is time to start looking for shorted or defective components. Something is wrong, somewhere, otherwise the fuse wouldn't have blown. Sometimes, actually rarely, fuses will "blow" for no apparent reason, simply because they are old.

However, in your case, I'd start looking for shorted transistors and the like if the second fuse blows. As I said above, if a fuse blows in a TV or anything else, you can just about bet that there is something shorted, a resistor gone way up in value upsetting bias voltages, etc. Normally, when a fuse blows, there is almost always an overload somewhere that must be tracked down and remedied before the device can be safely used again.

Do not, under any circumstances, jump the fuse or put in a larger fuse than the one that was in the set. Both dodges may get the set working, but it is a disaster waiting to happen if a short or an overload should occur anywhere in the TV. Non-technical people used to do this years ago with tube-type televisions, with disastrous results; in today's sophisticated sets with scan-derived power supplies and other complicated circuitry, jumping a fuse or replacing it with an overrated one can cause incredible damage -- not to mention starting a fire.
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Collecting, restoring and enjoying vintage Zenith radios since 2002

Zenith. Gone, but not forgotten.
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